Heat dissipation from a semiconductor IC die (“semiconductor die”) during operation is typically an important issue, especially as the density of devices on a semiconductor die continues to increase. Also, many semiconductor die now have combinations of high-power transistors and low-power transistors formed on a same die. Such high-power transistors tend to produce more heat as compared to low-power transistors. Furthermore, more system-on-chip (SOC) configurations are being used. Thus, there are often a wide variety of devices on a same semiconductor die. Some of the devices can handle and/or put out much more heat than nearby or neighboring devices on the same semiconductor die. Hence, the reliability and effectiveness of heat dissipation for a packaged semiconductor device may significantly affect the reliability and/or performance of the packaged device during operation.
Some wire-bonded packaged devices have thermal pads that include a surface (generally its bottom surface) that is exposed (not encapsulated) from the package that allows heat conduction away from the semiconductor die during operation to a board onto which the thermal pad is mounted (e.g., typically soldered) in its final application. For example, customers may mount the thermal pad to their sockets with solder similar to conventional device under test (DUT) pins/leads making the joint between the thermal pad and the board both electrically conductive as well as thermally conductive. For this reason in this arrangement, shorts between active (other than no-connect) DUT pins/leads and the thermal pad can result in shorting of the DUT and thus a defect in the DUT's application.